Rotary expansion-engine.



No. 867,581. 'PATEYNTED OCT. 8, 1907.

I E.HORN.

ROTARY EXPANSION ENGINE.

APPLICATION FILED JAN. 25, 1907.

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ATTORNEYS No.'867.581- -PATENTED 0018,1907.

v E. HORN. ROTARY EXPANSION ENGINE. APPLIOATI N FILED JAN. 25, 1907..

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nnrrnn STATES PATENT QFFIOE.

EMIL HORN, OF HILLYARD, WASHINGTON, ASSIGNOR OF ONE-THIRD TO JOSEPH A.STEELE AND ONE-THIRD TO WILLIAM E. JAMES, BOTH OF HILLYARD, WASHINGTON.

ROTARY EXPANSION-ENGINE.

Specification of Letters Patent.

Patented Oct. 8, 1907.

Application filed January 25,1907. Serial No. 354,025.

To all whom it may concern:

it known that I, EMIL HORN, a citizen of the United States, residing atHillyard, in the county of Spokane and State of Washington, haveinvented a new and useful Rotary Expansion-Engine, of which thefollowing is a specification.

This invention relates to a rotary engine of that type having aplurality of pistons against which steam or othermotive fluid issuccessively directed at full inlet pressure during a suitable portionof the revolution of each, after which the motive fluid acts expansivelyso that the total energy is extracted and high economy obtained.

The invention has for one of its objects to improve and simplify theconstruction and operation of prime movers of this character, so as tobe comparatively simple and inexpensive to construct, composed of fewparts which are easily maintained in order, thoroughly reliable andefficient in use, and of relatively high power for the quantity ofmotive fluid consumed.

Afurther object of the invention is the provision of a smooth and easyrunning engine in which the piston wings have an approximately uniformarea exposed to the working fluid throughout the stroke so that thesteam can act to the best advantage, each piston having only a singlewing on the front of which the steam acts to impel the piston while thesteam at exhaust pressure on the rear side of the wing is discharged asthe piston rotates, so that comparatively little back pressure isrequired to be overcome.

A further object of the invention is to provide a single rotary valvefor controlling the admission of motive fluid tothe various pistoncylinders and the exhaust of the fluid therefrom in any desired orderfor producing a comparatively uniform torque.

Afurther object of the invention is the employment of a suitablemechanism in connection with the rotary valve for starting and stoppingthe engine and control-- ling the admission of fluid to either side ofthe piston wings for propelling the engine in either a forward orreverse direction.

With these objects in view, and others, as will appear as the nature ofthe invention is better understood, the invention comprises the variousnovel features of construction and arrangement of parts, which will bemore fully described hereinafter, and set forth with particularity inthe claims appended hereto.

In the accompanying drawings, which illustrate one of the embodiments ofthe invention, Figure l is a vertical longitudinal section of an engineof the double piston type. Fig. 2 is an end elevation with one of theheads of the cylinder removed and the steam chest in section. Fig. 3 isan end view of the engine showing the controlling mechanism therefor.Fig. 4 is a perspective view of the controlling valve. Fig. 5 is afragmentary sectional view of the steam chest showing the inlet andexhaust ports.

Corresponding parts in the several figures are indicated throughout bysimilar characters of reference.

In the present instance, I have elected to illustrate the invention asapplied to a double piston engine, but I desire to-have it understoodthat the invention is not necessarily limited to this form since anydesired number of pistons may be employed. In a multiple piston engine,steam may be admitted to act on the pistons singly or in sets in asuccessive manner, so that an even and uniform torque will be produced.

Referring to the drawings, 1 designates the cylinder of the engine,which may be made in segments suitably secured together or cast in onepiece, as shown, and' fitted to the ends of the casing cylinder are theheads 2 bolted, or otherwise secured in place, the parts being carefullymachined so as to produce tight joints between them. The heads 2 areformed with hubs or bosses 3 at the shaft openings l-to serve asbearings for the shaft 5 of the engine. The casing is divided intoseparate piston chambers or compartments 6 by one or more partitions 7,one being shown in the present instance. This partition is preferablyformed integral with the cylinder 1 and has a central opening 8 throughwhich the shaft 5 extends. The inner surfaces of the heads and oppositesides of the partitions 7 arepreferably flat and carefully finished. Thecylindrical internal surfaces of the cylinder 1 are also carefullyfinished for the purpose of making a tight working fit with the pistonwings 9. In each compartment 6 is a piston 10 of the drum type whoseflat end surfaces are adapted to make a working fit with the fiat wallsof their respective compartments. Each piston is provided with a radialslot 11 which is open at the periphery thereof and at the end surfaces,and in each slot is mounted one of the wings 9. These wings are mountedto move in and out of their slots and bear at their outer ends againstthe internal surfaces of the compartments 6, and the sides of the wingsare adapted to make a working fit with the transverse flat walls of thecompartments', so that leakage of the motive fluid from points of highto points of low pressure will be prevented. In a double piston engine,the pistons are keyed to the shaft 5 in such a position that the wings 9are preferably located at diametrically opposite points with respect tothe shaft. Obviously, in an engine employing alarger number of pistons,the angular displacement of the wings may be varied, as desired, themain object being to enable the steam or other motive fluid to produce asuccession of regular impulses during each revolution so as to producesmooth running. The piston wings 9 are urged outwardly by helicalcompres sion springs 12 which are seated at their inner ends on thebottom of the slots 11 and engage at their outer ends in pockets 13 ofthe wings, Besides maintaining the wings in contact with the cylindricalwalls of the compartments 6, the springs permit the wings to moveinwardly as they pass under the dividing partitions 14 which separatethe inlet from the exhaust ends of the compartments 6.

At the top of the cylinder 1 is arranged a steam chest 15 which has acylindrical chamber 16 closed at its ends by the heads 17. Communicatingwith the chamber is an exhaust pipe 18 that forms a common exhaust forthe motive fluid from the compartments 6. In the chamber 16 is a rotaryvalve 19 which serves to control the admission and exhaust of motivefluid to the piston containing compartment. This valve is a tubularstructure having its bore 20 open at one end to communicate with thesteam supply pipe 21 that is connected With one of the heads 17 of thesteam chest. The opposite end of the valve is closed and provided with astem 22 extending axially'thereirom through the other head 17 forconnection at its outer end with a suit" able actuating mechanism.Around the stem 22 is arranged a stufling box 23 for preventing leakage.in the body of the valve are a pair of spaced inlet ports 24 and 25 forsupplying steam to the separate piston containing compartments, andextending around the body of the valve are the spaced arc-shaped ports26 and 27, as best shown in Fig. 4. Extending from the chamber of thevalve chest are two pairs of passages 28 and 29 communicatingrespectively with the two piston containing compartments 6. The passagesof each pair are slightly spaced apart and arranged with their lowerends disposed on opposite sides of the central plane passing through thedividing partition 14, so that the said passages communicate withopposite ends of their respective compartments 6. As shown by dottedlines in Fig. 2, the passages 29 are out of line with respect to thepassages 28, so that as the inlet port 24 is communieating with one ofthe passages 28, the inlet port 25 will be out of register with thecorresponding passage 29, so that steam will be admitted to thecompartments successively. As shown in Fig. 4, the admission ports 24and 25 are arranged in the same line, so that it is necessary to staggerthe passages 28 and 29. If desired, however, the passages can bearrangedin line with each other and the inlet ports staggeredaccordingly, so as to accomplish the same results. Since the upper endsof the passages 29 are arranged inwardly with respect to the upper endsof the passages 28, as shown in Fig. 2, the exhaust port 27 is somewhatlonger than the exhaust port 26 so as to obtain the proper relation ofthe parts.

When the parts are in the position shown in Fig. 2, live steam isadmitted through the port 24 and right hand passage 28 to the frontcompartment, so as to act on the wing of the piston therein. As thepiston rotates, the dead steam on the rear side of the wing is exhaustedthrough the other passage 28 and exhaust port 26 registering therewith.Simultaneously with the admission of live steam to this compartment, thesteam in the rear compartment is acting expansively on the piston wingtherein, since the inlet port 25 is out of register with the adjacentsupply passage 29. The cut-off of the steam may take place at anydesired point, pref-- erably aiter the wings have each moved through thefirst half of their strokes. Thus when the front piston has movedthrough half a revolution, the valve is aetuated so that the port 24will cut off the supply of steam and the port 25 open the supply to therear compartment. The exhaust ports are so proportionml that the steamon the rear side of the piston wings is free 1o exhaust continuously. Asthe wings come into eontact with the dividing partition 14, they areeach -n1oved inwardly and pass under and beyond the dividing partitionso as to be in position to begin another stroke. Simultaimously with thewings passing by their respective supply passages 28 and 29, theeontrolling valve is actuated so that a fresh supply of sin-am will beadmitted. it will thus be seen that live steam is acting on the pistonwings a )proximately throughout the complete revolution of the engineshaft, that is to say, live steam acts alternately on the pistons forabout hall a revolution and then expansively for the remaining portion.of the revolution. in order to prevent steam under high pressure frompassing directly to the exhaust passage, spring pressed packing rod 30is provided in the dividing partition H which bears against the drum 10in each comlmrtment. When it is desired to reverse the direction ofrotation, the valve 19 is turned to such a point that the. admissionports 24 and 25 will register with the 'rassages 28 and 29 at the lefthand side of the steam chest, as will be readily understood by referenceto Fig. 2. It will thus be seen that the passages 28 and 29 will be usedinterchangeably as supply and exhaust conduits eommunicating with theirrespective piston containing compartments. Furthermore, the constructionof the. valve is such that it readily lends itself for use in eonnectionwith engines of any desired number of pistons.

The valve actuating mechanism shown in Fig. 1 comprises an arm 31secured to the valve stem .22 and an eccentric rod 32 connectedtherewith and actuated by an eccentric 83 on the shait 5. By this means,the valve 19 is rocked back and iorth so as to control the alternatesupplies oi steam to the two pistons. This form of actuating mechanismis suitable in that class of work where continuous rotation in onedirection is desirable, as, ior instance, in mills where. machinery doesnot require to be reversed.

To render the engine reversible, the mcclntnism shown in Fig. 3 isemployed. This comprises a link 34 which is shiftable along thesegnu-ntal block 85 which engages in the slot of the link and suitablyattached to the valve stem. The link 4 is oscillated by the eccentricrod 36 connected with the arm 37 of the link, and connected with theeccentric 38 by the strap 39. The link 34 is shiited by the operatinglever 40 which is oi the bell crank form and Iulerumed at l l. at asuitable point on the engine asing. The short arm 01 the lever isconnected with the link by the member 42 which is pivoted to the linksaddle 13. Associated with the operating lever is a toothed sector 44which is engaged by the latch 45 on the operating lever. This latch isactuated by the spring pressed grip 46. \Vhcn the parts are in theposition shown. the engine is idle, since the valve has been shifted tosuch a point that the inlet ports thercol do not register with any ofthe passages communicating with the piston compartments. When. theoperating lever is moved to one side or the other to the neutralposition, the engine will be driven in a oi-ward direction, or

reverse, and by returning the lever to its central position, the enginewill be stopped.

For automatically controlling the speed of the engine, the throttlevalve 47 of any approved construction isarranged in the steam supplypipe 21, and associated therewith is a speed responsive device 48 thatis drivenirom the main shaft 5 by the belt and pulley transmission 49,as shown in Fig. 1. By this means, the supply or steam to the severalinlet ports of the controlling valve 19 is regulated in accordance withchanges in load oil the engine, so that a constant speed can bemaintained.

From the foregoing description, taken in connection with theaccompanying drawings, the advantages of the construction and of themethod of operation will be readily apparent to those skilled in the artto which the invention appertains, and while I have described theprinciple of operation oi the invention, together with the apparatuswhich I now consider to be the best embodiment thereoi, I desire to haveit understood that the apparatus shown is merely illustrative, and thatvarious changes may be made, when desired, as are within the scope ofthe claims.

What is claimed is 1. In a rotary engine, the combination of a casingdivided into compartments, a drum piston in each compartment, wings onthe pistons angularly displaced one with respect to another, and a shaftfor the pistons, with a single valve for admitting and cutting off themotive fluid to the front side of the Wings and exhausting the fluidfrom the rear side of the wings, an automatically actuated throttle forregulating the supply of motive fluid to the valve, and a reversingmechanism connected with the valve.

2. The combination of a rotary engine comprising a casing divided intocompartments, and pistons therein, with a cut-off valve mechanismtherefor, said mechanism comprising a steam chest, a set of spacedpassages between each compartment of the engine casing and the chest, arotary valve in the chest comprising a hollow body, radially extendingports in the valve each adapted to communicate with one of the passagesof each set, an areshaped port in the valve for the other passage ofeach set, a pipe communicating with the hollow of the valve and all ofthe radial ports thereof, and a second pipe communicating with the steamchest and the arc-shaped ports of the valve.

3. The combination of a rotary engine comprising a casing divided intocompartments, pistons therein, and a shaft for the pistons, with acut-oft valve mechanism therefor actuated by the shaft, said mechanismcomprising a valve chest mounted on the casing, a plurality of sets ofpassages extending from the chest to each compartment of the casing, asingle rotary valve in the chest which is hollow at its center, sets ofinlet and exhaust ports each arranged to communicate with one of thesets of passages, heads on the chest, a supply pipe connected with oneof the heads and communicating with the hollow of the valve, an exhaustpipe communicating with the chest, a stem on the valve extending throughthe other head of the chest, means between the engine shaft and stem forlocking the valve, and a device for adjusting the valve to reverse theengine or stop the same. i

In testimony that I claim the foregoing as my own, I have hereto aIIiXedmy signature in the presence of two witnesses.

EMIL HORN.

Witnesses W. E. JAMES, J. A. S'rEnLn.

